title: Cardiovascular control and stabilization via inclination and mobilization during bed rest.
abstract: Cardiovascular deconditioning has long been recognized as a characteristic of the physiological adaptation to long-term bed rest in patients. The process is thought to contribute to orthostatic intolerance and enhance secondary complications in a significant way. Mobilization is a cost-effective and simple method to maintain the cardiovascular parameters (i.e., blood pressure, heart rate) stable, counter orthostatic intolerance and reduce the risk of secondary problems in patients during long-term immobilization. The aim of this project is to control the cardiovascular parameters such as heart rate and blood pressure of bed rest patients via automated leg mobilization and body tilting. In a first step, a nonlinear model predictive control strategy was designed and evaluated on five healthy subjects and 11 bed rest patients. In a next step, a clinically feasible study was conducted on two patients. The mean values differed on average less than 1 bpm from the predetermined heart rate and less than 2.5 mmHg from the desired blood pressure values. These results of the feasibility study are promising, although heterogeneous disease etiologies and individual medication strongly influence the mechanically induced reactions. The long-term goal is an automation of the control of physiological signals and the mobilization of bed rest patients in an early phase of the rehabilitation process. Therefore, this new approach could help to strengthen the cardiovascular system and prevent secondary health problems arising from long-term bed rest.
authors.affiliation: Sensory-Motor Systems Lab, Department of Health Science and Technologies (HEST), Institute of Robotics and Intelligent Systems (IRIS), ETH Zurich, Tannenstrasse 1, 8092, Zurich, Switzerland.
authors.forename: Martin
authors.initials: M
authors.lastname: Wieser
authors.forename: Stefan
authors.initials: S
authors.lastname: Gisler
authors.forename: Amirehsan
authors.initials: A
authors.lastname: Sarabadani
authors.forename: Rafael M
authors.initials: RM
authors.lastname: Ruest
authors.forename: Lilith
authors.initials: L
authors.lastname: Buetler
authors.forename: Heike
authors.initials: H
authors.lastname: Vallery
authors.forename: Verena
authors.initials: V
authors.lastname: Klamroth-Marganska
authors.forename: Margret
authors.initials: M
authors.lastname: Hund-Georgiadis
authors.forename: Morena
authors.initials: M
authors.lastname: Felder
authors.forename: Josef L
authors.initials: JL
authors.lastname: Schoenberger
authors.forename: Clemens
authors.initials: C
authors.lastname: Gutknecht
authors.forename: Robert
authors.initials: R
authors.lastname: Riener
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001510:Bed Rest / Q000009:adverse effects*; D001513:Beds; D001794:Blood Pressure / Q000502:physiology; D018493:Cardiovascular Deconditioning / Q000502:physiology; D002319:Cardiovascular System / Q000503:physiopathology*; D005260:Female; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D055815:Young Adult